# # # print("hello world")
# #
# # print(2 % 5)
#
# print(2 + 3)
# print(2 * 3)
# print(2 / 3)

# avg = (67.5 + 89.0 + 12.9 + 32.2) / 4
# total = (avg - 67.5)**2 + (avg - 89.0)**2 + (avg - 12.9)**2 + (avg - 32.2)**2
# print(total / 3)
#
# b:int = 20
# a:int = 10

# a = 10
# b = 20

# a = 10 b = 20

# a = 10
# print(type(a))  # <class 'int'>

# a = 0.5
# print(type(a))  # <class 'float'>

# a = 'hello'
# print(type(a))  # <class 'str'>

# # 二者没有区别，都表示字符串
# str1 = 'hello'
# str2 = "hello"

# # 打印一句话：My name is "zhangsan"
# s = 'My name is "zhangsan"'
# print(s)
# s = """My name 'is' "zhangsan"""""
# print(s)

# s = "hello world"
# print(len(s))  # 11

# s1 = "hello"
# s2 = "world"
# print(s1 + 3)  # helloworld

# s = "hello"
# print(s + 2022)

# a = True
# b = False
# print(type(a), type(b))  # <class 'bool'> <class 'bool'>

# a:int = 10
# print(type(a))
#
# a = "hello"
# print(type(a))
#
# a = True
# print(type(a))

# # 记录数据总和
# sum = 0


# print("hello")

# print("hello")  # hello

# a = 10
# print(a)  # 10
#
# b = True
# print(b)  # True

# num = 10
# print(f'num = {num}')

# num = input("请输入一个数字：")
# print(type(num))

# a = int(input("请输入第一个整数："))
# b = int(input("请输入第二个整数："))
# print(f'a + b = {a + b}')

# print(-19 % 2)

# print(4 ** 2)  # 16
# print(4 ** 0.5)  # 2.0

# # 地板除法（取整除法），会针对计算的结果进行“向下取整”
# print(7 // 2)   # 3
# print(-7 // 2)  # -4

# print(10 / 0)

# print(1 / 2)  # 0.5

# print(0.1 + 0.2 == 0.3)  # False

# print(0.1)
# print(0.2)
# print(0.1 + 0.2)
# print(0.3)
#
# a = 0.1 + 0.2
# b = 0.3
# print(-0.000001 < (a - b) < 0.000001)  # True

# print(10 > 20 and 10 / 0 == 1)  # False
# print(10 < 20 or 10 / 0 == 1)   # True

a = 10
++a
a++
